The use of lights and other illuminating devices with glasses is known. Generally, however, they have not been very well adapted for use with reading glasses. As is known, these types of glasses typically are not worn all the time, and are subject to being frequently taken off and put back on. On the other hand, when reading glasses are worn, they should be comfortable enough to encourage their use so that people are not avoiding their glasses and instead straining their eyes to read.
Incandescent light bulbs commonly have been proposed for use with lighted glasses. Unfortunately, such lighting devices generate a significant amount of heat Smaller, less powerful incandescent lights still may make the wearer feel quite uncomfortable after even a short while due to the proximity of the light source and the wearer's face. Further decreasing the size of the incandescent lights, to the point where the wearer is comfortable, may cause light output to be very dim and therefore unusable for illuminating reading material that are held at distances optimal for reading.
For example, if reading distance after using corrective lenses for those in need of vision correction of ordinary size text, e.g. 10 or 12 point font, is optimally ten to eighteen inches from the eyes, a light that is capable of brightly illuminating the pages within that range of distances is necessary for ensuring comfort in reading in dimly lighted areas. However, a lower intensity light bulb, which may be preferable to reduce heat or increase battery life, may result in less than optimal lighting at the optimal reading distance, causing eye-strain and discomfort. In other words, the lower intensity of the light source will result in a decrease in the brightness of the light on the page so that the text to be read is only dimly lit.
The use of fiber optic lighting devices instead of incandescent light bulbs is known. In such devices, optical fibers are bundled together to create a light producing device. The nature of fiber optics is such that there is no heat generated at the point where the light is typically transmitted; that is, adjacent the user's temple. Unfortunately, such devices suffer from a rather major limitation. Namely, a very intense and powerful light source must be available to provide light to the optical fibers. As such, head gear such as worn by surgeons having a fiber optic lighting device must at all times stay tethered to a fiber optic light source, which severely restricts the mobility of the user and thus the ease of use of the headgear. A portable light source that stays connected to the fiber optic light head via electrical cables is less than desirable in terms of the need to be able to conveniently carry the light source, and the inconveniences associated with dangling connecting lines.
An additional problem that exists with fiber optic devices, as well as incandescent lighting devices, is rapid battery consumption. Incandescent light bulbs are known to consume large amounts of power. Similarly, a fiber optic device, since it requires a strong lighting source, also requires a large amount of power. As a result, the user is be forced to change batteries often or stay tethered to a constant power source or light source.
Another disadvantage in prior art lighting devices is the manner in which surfaces are illuminated. Lighting devices used in the medical field generally produce a single fixed narrow beam of light to brightly illuminate the particular stationary body area on which the doctor may be operating. However, such a single narrow beam would not be particularly helpful in reading textual material as the beam would have to be continually shifted across the page being read. On the other hand, lights used with glasses generally tend to be very inefficient in their use of the light they generate as large amounts of light are cast beyond the field of view of the glasses. Adjustable lights are less than desirable as they require a user to make sure the lights are properly positioned each time the glasses are used.
Accordingly, there is a need for lighted glasses that are optimized for use in poorly lit or dim areas. More particularly, reading glasses having lights that are arranged to direct an optimum amount of light to the area where it is required most, i.e. the reading area, is needed. Further, lights that are very compact and lightweight, while still providing the necessary lighting strength and having a sufficiently long life for the power source that power these lights would be desirable.